Both devices will boast several of the features available on Samsung's petite Galaxy S4, which launches later this spring. Among them: Group Play for sharing content across multiple devices, S Translator for translating content by text or voice, and WatchON to transform the smartphone into a TV remote control. The smartphone will also run the latest version of Google's Android operating system.

It's not clear when -- or if -- the Galaxy Mega will make its debut in the U.S. Samsung says the phone will be available globally starting this May with Europe and Russia, followed by a gradual rollout elsewhere.

The Galaxy Mega stretches the limits on how far consumers are willing to go on screen size. Samsung's Galaxy Note II features the largest screen for a smartphone in the U.S. at 5.5 inches. However, there are benefits to having the larger screen, such as for viewing videos and photos.